The invention relates to strain relief and, in particular, to a staple strain relief which cooperates with a connector back shell to provide strain relief for a variety of cable sizes received in the back shell of an electrical connector.
When electrically terminating conductors or cables to an electrical connector, strain relief arrangements are known which minimize forces placed on the electrical terminations. The cable is secured to the housing to transfer thereto forces to which the cable is subjected.
As multiple conductor cables of smaller size are made, strain relief becomes more critical. Smaller electrical connections are more sensitive to strain forces, less space available for the leads decreases flexibility, and the multiplicity of conductors pose interference problems between the various conductors which further decreases flexibility. In such connectors, rigidity is desirable in the strain relief system.
Good strain relief of a cable terminated to a connector requires proper compression of the cable. Too much compression can reduce the cross-sectional area of conductor strands or in the extreme break conductor strands while too little compression of the cable permits undesirable movement of the cable within the strain relief structure. The clamping member receiving force from the cable should also be rigid for all directions of force applied by the cable.
Some prior art strain relief systems have used latching segments in serrated form which engage corresponding segments only at stepped locations. Those strain relief systems, which require movement of fingers in a direction perpendicular to the cable axis, lock into place only after excessive compression of the cable. An excessively compressed cable will not fully spring back even when the cable is not damaged by the overcompression. The full effect of the compression is therefore not achieved. Such strain relief systems are also susceptible to movement of the connector in a direction transverse to the latching teeth.
Various bolted strain relief systems have been used, but they are more time consuming to install. Bolted strain relief systems also typically have multiple parts that must be attached to a connector and also permit movement around the bolt holes.